Dyeing and light stabilizing nylon yarns with sulfonated dyes; sterically hindered phenols, and alkylnaphthalene sulfonates with or without other ultraviolet light absorbers



United States Patent M DYEING AND LIGHT STABILIZING NYLGN YARNS WlTHSULFONATED DYES; STERI- CALLY HHNDERED PHENGLS, AND ALKYL- NAEHTHALENESULFONATES WITH OR WITHUUT OTHER ULTRAVIOLET LIGHT ABSURBERS JosephAloysius Brooks, Wilmington, DeL, assignor to E. I. du Pont de Nemoursand Company, Wilmington,

DeL, a corporation of Delaware No Drawing. Filed Feb. 12, 1964, Ser. No.344,204

11 Claims. (Cl. 817) ABSTRACT OF THE DISCLQSURE Nylon yarns are dyedwith a solution of a water soluble sulfonated acid dye, a2,6-dialkyl-4-phenyl phenol, an alkylor aralkyl-substitute naphthalenesulfonic acid ammonium or alkali metal salt. In addition, ultravioletlight absorbers, such as hydroxyphenyl-benzotriazole,hydroxybenzophenone, or aromatic substituted acrylonitrile can be usedin the solution.

This invention relates generally to textile fibers and, moreparticularly, to a process for dyeing nylon yarns.

It is well known that streaking occurs in acid-dyed fabrics constructedwith synthetic linear polyamide yarns, especially with continuousfilament polyarnide yarns. Therefore, the level-dyeing disperse dyes arebroadly used for nylon fabrics; but not all disperse dyes haveacceptable lightfastness. With those disperse dyes that provideacceptable dye lightfastness, a severe problem in fading results becauseof the N0 and the O conventionally in the air. Level dyeing can beaccomplished with acid dyes that are chemically stable to N0 and 0 byusing anionic leveling agents, but such acid dyeing processes do notproduce lightfast fabrics. In the acid dyeing of carpets, an additionalproblem exists in the fugitive stain from the jute backing, and thisproblem is evidenced by both streakiness and insufiicient lightfastness.

The principal object of this invention is to provide superior level-dyedpolyamide yarns.

A further object of this invention is to provide nylon yarns that arelevel-dyed, lightfast, and stable to gaseous atmospheric conditions thatare recognized to fade disperse-type dyes.

Other objects will appear hereinafter.

These and other objects are achieved in a process for dyeing polyamideyarn in a dye bath containing (1) sulfonated, water soluble, acid dyeswith molecular weight less than 850; (2) an anti-oxidant which is aphenolic compound of the formula a naphthalene compound Patented Jan.16, 1968 wherein R is a monovalent substituent radical selected from thegroup consisting of propyl, isopropyl, butyl (normal, secondary andtertiary), amyl (normal, secondary and tertiary), and aralkyl, m is 1-3and R" is a monovalent radical selected from the group consisting of NHand alkali metal cations, each of the substituent radicals -R and -SO R"being attached at one of positions 1-8.

1n the preferred process embodiment, the aforementioned dye bath alsocontains (4) a p-hotostable, ultraviolet light absorber, said absorberbeing a member of one of the classes consisting ofhydroxyphenylbenzotriazoles, hydroxybenzopheno-nes, and aromaticsubstituted acrylonitriles, and being readily absorbed by polyamideyarn.

The phenolic compound is readily absorbed by polyamide yarns, remainssubstantially colorless during the dyeing process, and remainscolor-stable after dyeing. The bulky alkyl groups, R and R havegenerally at least 3 to 8 carbon atoms and are branched at the carbonatom alpha to the phenol ring. The preferred compound is2,6-di-tert-butyl-4-pheny1 phenol. The phenolic compound is preferablyadded as an emulsion.

The examples illustrate the advantages of the process in the dyeing ofp-olyamide yarns, particularly in dyeing finished goods (such ascarpets) containing nylon yarns and in dyeing polyethylene oxide (PEG)modified nylon yarns and fabrics. It is known that the tendency offilaments prepared from synthetic linear polyamides to ac quireundesirable static charges has been overcome and that soil resistancehas been enhanced by blending with the polyamide at least 2% by weightof a polyethylene oxide (PEO), prior to forming filaments thereof. Afterdyeing, however, the color of yarns and fabrics prepared fromPEG-modified nylon filaments still can weaken at process embodimentwherein the dyes, antioxidant, level ing agent and ultraviolet lightabsorber are combined in a dye bath. Examples I and VI show thepreferred method of adding the antioxidant as an emulsion, resulting inunexpectedly superior level-dyed, lightfast, carpeting that is stable toatmospheric conditions. The second example shows the benefits of havingonly the acid dyes, leveling agent and phenyl-phenol in the dye bath.Example III shows unsatisfactory lightfastness obtained when theantioxidant is omitted. The fifth example shows the unsatisyarn is dyedby the process of this invention. All percentages, except Whereotherwise noted, are based on carpet weight. Also, for convenience, theapproximate Metric System equivalent of the English units have beengiven in parentheses.

EXAMPLE I Approximately 700 square yards (585 square meters), weighing1340 pounds (600 kilograms), of jute-backed carpeting comprising 21ounces per square yard (496 r grams/square meter) of face nylon istufted with 3700- al. in U.S. Patent 3,005,251. Said carpeting is placedin a denier, 204-trilobal, continous-filament, jet bulked yarn,melt-spun from poly(hexamethylene adipamidefiiake. The yarn is jetbulked with the jet taught by Hallden ct nominally 15-foot-wide (4.56meters) beck containing approximately 5500 gallons (21,000 liters) of ascouring bath which is an alkaline aqueous solution at 130 F. (54 C.)comprising 1) 0.1% Antifoam B (a silicone emulsion to reduce foaming),(2) 0.25% the condensation product of 15-25 mols of ethylene oxide with1 mol of either a long-chain fatty alcohol containing 12-18 carbon atomsor a mixture of fatty alcohols each containing 12-18 carbon atoms, and0.15% the sodium salt of the sulfate ester of either a long-chain, fattyalcohol containing 12-18 carbon atoms or a mixture of fatty alcoholseach containing 12-18 carbon atoms, (3) 0.75 NaOH, and (4) 1.5% of asolution of 30 weight parts H and 70 weight parts H O. This solution israised to 140 F. (60 C.) and then 0.25% sodium dichromate is added andnext, the temperature of this resultant dichromate solution is raised to200 F. (90 C.) at a rate of 3 F. (1.66 C.) per minute. Then, thescouring bath is dropped, the beck is filled again with 5500 gallons(21,000 liters) of water at 130 F. (54 C), and this rinse bath is runfor 10 minutes and then dropped.

The heck is refilled, this time with a bath of 5500 gallons (21,000liters) of water and the carpeting is leveldyed in said beck accordingto the following procedure.

(1) Set the dye-bath at not more than about 80 F. (27 C.) and add 1.75pounds (794 grams) of Antifoam B.

(2) In a separate piece of equipment, provide an aqueous solution of11.2 pounds kilograms) the ocsodium sulfonate of disec-buty1naphthalene, and 35 pounds (16 kilograms) of phosphoric acid; and thensyphon this solution to the heck to attain a pH of about 3.3 in saidbeck.

(3) Dissolve in 50 gallons (189 liters) of water in another piece o-fequipment, a mixture of 0.25% CI. Acid Brown [sodiumP-[4-(diethylarnino)hydroxy-l-naphthylazo]benzenesulfonate], 0.04% CI.Acid Red 57 [sodium 6 amino-5 [O-(ethylphenylsulfamoyl)phenylazo]4-hydroxy-2-naphthalenesulfonate], and 0.041% C.I. Acid Blue 40 [0.1.62125], to make a cocoa shade, and continuously add this solution to theheck over a period of minutes.

(4) Run this bath for 15 minutes at 80 F. (27 C.) and then raise thetemperature to 140 F. (60 C.) at a rate of 3 F. (l.66 C.) per minute.

(5) Dissolve in about 12 gallons (45 liters) of water in a separatepiece of equipment, 70 ounces (2 kilograms) of NaOH, 1.2 ounces (34grams) of the condensation product of 15-25 mols of ethylene oxide withone mol of either a long-chain fatty alcohol containing 12-18 carbonatoms or a mixture of fatty alcohols each containing 12-18 carbon atoms,and 7 pounds (3.2 kilograms) of 2-(2-hydroxy-5'-metl1ylphenyl)benzotriazole. This solution is brought to a boil to form thesodium salt of the benzotriazole and then diluted to about 40 gallons(150 liters) of solution to reduce solution temperature to about 120 F.(49 C.).

(6) To the 140 F. (60 C.) bath (Step 4), continuously add the cooledsolution of Step (5) to the heck over a period of 15 minutes. The pH ofthe dye bath in the beck is now about 3.7.

(7) Raise the dye-bath temperature to 180 F. (82 C.) at arate of 3 F.(1.66 C.) per minute.

(8) Add 13.4 pounds (6 kilograms) of 2,6-di-tertbuty1-4-phenyl phenol asan emulsion. Said emulsion is made up by first preparing 61 parts byweight of A and 39 parts by weight of B. Part A consists of 24 parts byweight of 2,6-di-tert-butyl-4-phenyl phenol, 36 parts by weight oftoluene, and 1 part by weight of oleic acid. Part B consists of parts byweight of a 10% ammonium caseinate solution in water, 1.2 parts byweight sodium salt of technical lauryl alcohol, 1 part by weight KOH,and 6.8 parts by weight water. Then A is added to B with high speedagitation to provide a stable, water-dispel-sable, antioxidant for thedye bath.

(9) Add approximately 4 pounds (1.8 kilograms) of phosphoric acid toattain a pH of approximately 3.7 in the dye bath.

(10) Raise the temperature of the dye bath to 205 F. (96 C.) at the rateof 3 F. (166 C.) per minute.

(11) Dye for 1 hour at a temperature as close as possible to 205 F. (96C.).

(12) Drop the dye bath, rinse the carpeting well, extract the rinsewater, and dry the carpeting at about 280 F. (138 G). Then latex-backthe carpeting at 285-300 F. (140-150 C.).

This carpeting is observed to be attractively level-dyed, substantiallystreak-free, and desirably unstained by the jute-backing. Then it istested for lightfastness by exposure to Florida sunlight for 45 sunhours. The Gray Scale rating, 4, resulting from such an exposure tosunlight, indicates a sufficiently small shade change to rate thecarpeting to have good lightfastness. For an exposure to Floridasunlight for 65 sun hours, the Gray Scale rating is between 4 and 3. Inthe Gray Scale (described in Standard Methods for the Assessment of theColor Fastness of Textiles by the Society of Dyers & Colorists, 19Picadilly, Bradford, Yorks, England) 5 denotes no shade change and 1denotes the greatest (an unacceptable amount) shade change. A unitincrease in the Gray Scale denotes a two-fold improvement inlightfastness.

The dyed carpetin of this example is also tested for chemical fading.For testing stability in 0 the dried and finished dyed carpeting isplaced in a commerical ozone, oven maufactured by Ozone Research &Equipment Corporation, 3840 N. 40th Ave., Phoenix, Ariz. Said ovenexposes the carpeting to 10 parts of O in one hundred million parts ofair for 120 hours at 95 F. (35 C.) and between and relative humidity.The Gray Scale rating, 4, resulting from such an exposure to 0 indicatesa sufiiciently small shade change to rate the dyed carpeting to bestable to atmospheric conditions wherein O is present. For testingstability to N0 the dried and finished dyed carpeting is testedfollowing the American Association of Textile Chemists and ColoristsTest No. 23-1962 for 2 cycles and then the Gray Scale rating is 4, toindicate sufficiently small shade change to rate the dyed carpeting tobe stable to atmospheric conditions wherein N0 is present.

EXAMPLE II 152 grams of face nylon yarn is used to prepare jutebacked,tufted carpeting comprising 22 ounces per square yard 520 grams/squaremeter) of said face nylon. Said yarn is 3700-denier, 240 trilobal,continuous-filament, jetbulked yarn, melt-spun from poly(hexamethyleneadipamide)flake. The yarn is jet-bulked with the jet taught by Halldenet al. in US. Patent 3,005,251. Said carpeting is placed in a laboratorybeck containing an alkaline aqueous solution comprising 0.25% thecondensation product of 15-25 mols of ethylene oxide with 1 mol ofeither a longchain fatty alcohol containing 12-18 carbon atoms or amixture of fatty alcohols each containing 12-18 carbon atoms, and 0.15%the sodium salt of the sulfate ester of either a long-chain fattyalcohol or a mixture of fatty alcohols each containing 12-18 carbonatoms, and 0.75% NaOH. Said alkaline aqueous solution is heated to F.(54 C.) at a rate of about 3 F. (1.66 C.) per minute and then 1.5 of asolution 30 weight parts of H 0 and 70 weight parts H O is added to thelaboratory beck. The resultant solution is now heated to F. (60 C.) at arate of about 3 F. (1.66 C.) per minute. Optionally, 0.25 sodiumdichromate is added at this point. Heating is continued at a rate of 3F. (1.66 C.) per minute up to a temperature of 200 F. (93 C.). Then thescouring bath is dropped, and the carpeting is rinsed twice with water.

The laboratory heck is refilled with water, and the carpeting islevel-dyed in said laboratory beck according to the following procedure:

(1) Set the dye bath at not more than 100 F. (38 C.)

and add 0.75% of the u-sodium sulfonate of di-sec-butyl naphthalene, and1% 2,6-di-tert-butyl-4-phenyl phenol in 30 cc. acetone.

(2) Run this bath for 5 minutes; then slowly add as a mixture 0.5% CI.Acid Brown 10, 0.06% CI. Acid Red 57, and 0.05% CI. Acid Blue 40.

(3) Run this bath for an additional 5 minutes at 100 F. (38 C.) and thenadd diluted phosphoric acid dropwise for about 15 minutes to attain a pHof 4.0 and then bring the bath to a boil at a rate of about 2-3 F. (1.11-1.66 C.) per minute.

(4) Run this bath for 45 minutes and then add cc. of a 10% phosphoricacid solution to obtain a pH of about 3.1.

(5) Complete the dyeing for one hour at a temperature as close to theboil as possible.

(6) Drop the dye bath, rinse the carpeting twice with warm water,extract, and finally dry the carpeting at about 275 F. (135 C.).

This carpeting is observed to be substantially streakfree and is testedfor lightfastness by exposure to the light of a Xenon arc in air in anAtlas Xenon Weather- Ometer (Model 60-WR) to simulate 80 sun hours. TheGray Scale rating for the carpeting of this Example II is 2.

EXAMPLE III Example II is repeated except that in Step 1 of theleveldyeing procedure, instead of 2,6-di-tert-butyl-4-phenyl phenol,0.15% the condensation product of -25 mols of ethylene oxide and 1 molof either a long-chain fatty alcohol containing 12-18 carbon atoms or amixture of fatty alcohols each containing 12-18 carbon atoms is added.The Gary Scale rating observed in the carpeting of this Example III is 1for simulated 80 sun hours.

EXAMPLE IV Example II is repeated except that no 2,6-di-tert-butyl-4-phenyl phenol is added in Step (1), and instead in Step (5 of thelevel-dyeing procedure, 1.5 on weight of yarn of2,6-di-tert-butyl-4-phenyl phenol in 30 cc. of acetone is added dropwiseand then 0.5% 2-(2'hydroxy-5'-methyl phenyl)benzotriazole in 30 cc.acetone is also added dropwise. Also, in Step (5 the dyeing is 30minutes. The Gray Scale rating observed in the carpeting of this ExampleIV is 3 for 80 simulated sun hours.

EXAMPLE V Example II is repeated except that instead of2,6-ditert-butyl-4-phenyl phenol, 1% on weight of yarn of 2,6-di-tert-butyl-4-methyl phenol is added in Step (1). Fur thermore, thedyeing in Step (5) is completed in only 30 minutes. The Gray Scalerating observed in the carpet of this Example V is 1 for 80 simulatedsun hours.

EXAMPLE VI 159 Grams of face nylon are used to prepare carpeting similarto the carpeting prepared for Example I1, and this carpeting is scouredand rinsed in a laboratory beck in the same manner as is the carpetingfor Example II. Then the laboratory beck is refilled with water, and thecarpeting is level-dyed in said laboratory beck according to thefollowing procedure:

(1) Set the dye bath at not more than 100 F. (38 C.), add 0.15% thecondensation product of 15-25 mols of ethylene oxide with 1 mol ofeither a long-chain fatty alcohol containing 12-18 carbon atoms or amixture of fatty alcohols each containing 12-18 carbon atoms, and thenadd 18 grams of dispersed emulsion in 20 parts of water at 170 F. (77C.). Said dispersed emulsion is made as follows:

A melt at 221 F. (105 C.) is made of a mixture of 24 grams of2,6-di-tert butyl-4-phenyl phenol, 12 grams of 2-(2-hydroxy-5'-methylphenyl)benzotriazole, and 12 grams of the condensation product of l-Smols of ethylene oxide with 1 mol of either a long-chain fatty alcoholcontaining 12-18 carbon atoms or a mixture of fatty 6 alcohols eachcontaining 12-18 carbon atoms. Twelve grams of said melt is added, withmixing, to 48 grams of a 15% Water solution (cooled in water to 50 F.(10 C.)) of the a-sodium sulfonate of di-sec-butyl naphthalene to form athick creamy dispersed emulsion.

(2) Run this bath for 10 minutes; then add slowly as a mixture 0.5% CI.Acid Brown 10, 0.06% CI. Acid Red 57, and 0.05% CI. Acid Blue 40.

(3) Run this bath for an additional 10 minutes at F. (38 C.) and thenadd 2% acetic acid to attain a pH of 4.5 and then bring the bath to aboil.

(4) Boil for 45 minutes and then add phosphoric acid solution to obtaina pH of about 3.0.

(5) Continue the dyeing for about 30 minutes more at a temperature asclose to boil as possible. The pH is then about 3.2.

(6) Drop the dye 'bath, rinse the carpeting twice with Warm water,extract, and finally dry the carpeting at about 275 F. C.).

This carpeting is observed to be substantially streakfree, and is testedfor lightfastness as is the dyed carpeting of Example II. The Gray Scalerating for the carpeting of this Example V1 is 3.

EXAMPLE VII Three griege skeins of 3700 denier, 204 trilobal,crosssection filaments, zero twist, semi-dull luster, bulked yarnconstructed of filaments spun from a 95/5 melt blend ofpoly(hexamethylene adipamide)/polyethylene oxide ether glycol of 20,000molecular weight are scoured for 20 minutes at F. (60 C.) in a 30:1aqueous bath previously set at 80 F. (27 C.) with 0.06% of thecondensation product of 15-25 mols of ethylene oxide with one mol ofeither a long-chain fatty alcohol containing 12-18 carbon atoms or amixture of fatty alcohols each containing 12-18 carbon atoms, and 0.2.5tetrasodium pyrophosphate. After rinsing, one of the skeins is leveldyedin a dye-bath according to the following procedures:

(1) Set the dye bath, containing the skein, at not more than 80 F. (27C.) with 0.75% the OL-SOdlllIn sulfonate of di-sec-butyl naphthalene,and 0.75% Lyocol HW, a leveling agent which is an anionic, aromaticsulfonate.

(2) Run this bath for 10 minutes and then add 0.5% of2-(2-hydroxy-5-methyl phenyl)benzotriazole, and 1%2,6-di-tert-butyl-4-phenyl phenol dissolved in 30 cc. acetone.

(3) Run this bath for 10 minutes and then slowly add, as a mixture, 1%Cl. Acid Brown 1 0, 0.12% CI. Acid Red 57 and 0.08% Ct. Acid Blue 58[0.1. 62125] dyes.

(4) Run this bath for an additional 10 minutes at 80 F. (27 C.).

(5 Slowly add sufiicient acetic acid (concentrated) to give a pH ofabout 4.5.

(6) Raise the bath temperature to 130 F. (54 C.) at the rate of about 1F. C.) per minute and then run this bath again for 10 minutes.

(7) Raise the bath temperature to F. (71 C.) at the rate of about 1 F.C.) per minute.

(8) Raise the bath temperature to 200 F. (93 C.) at the rate of about 2F. (1.11 C.) per minute, adding 1.5% phosphoric acid at the end of 30minutes.

(9) Dye for 1 hour at a temperature as close to 200 F. (93 C.) aspossible.

(10) Cool back to 180 F. (822 C.) slowly, rinse well, extract, and thendry the yarn at 280 F. (138 0).

Another skein is similarly dyed except that no ultraviolet lightabsorber is added in Step (2), although the phenyl phenol is present.The third skein is similarly dyed except that Step (2) is omitted.

These three dyed and dried skeins are tested for dye light-fastness byexposure to the light of a Xenon arc in air in an Atlas XenonWeather-Ometer (Model 60- WR) to simulate 80 sun hours. They are thencompared with otherwise identical, unexposed skeins. The results areshown in the table below with a numerical rating according to the GrayScale:

ultraviolet light absorber 2 Dyed with neither the ultraviolet lightabsorber nor the phenyl phenol 1 The above example indicates that theeffect of the phenolic antioxidant and the ultraviolet light absorber ismore than additive because, when they are both present, the improvementis more than twice the improvement due to the presence of the phenolicantioxidant alone.

As hereinbefore indicated, Example I specifies the preferred processembodiment wherein the ultraviolet light absorber is added to the dyebath in the form of a sodium salt with subsequent regeneration to thefree phenol. The temperature is raised, and then2,6-ditert-buty1-4-phenyl phenol is added as an oil-in-Water emulsion.Finally, the carpeting is rinsed, dried and latex-backed. Example VIillustrates another process wherein the antioxidant is in the form of anemulsion.

Examples II, IV and VII indicate that the process is likewise operablewhen the antioxidant is added in acetone. Example VII furtherillustrates the beneficial results obtained on PEO-modified yarns.

The process of this invention has utility for fabrics as well as foryarn, for bulked, as Well as for unbulked, yarn, for round, as well asfor unround, filaments, and is particularly useful in dyeing carpets,rugs and upholstery, Whether or not the yarn is FED-modified.

The preferred leveling agent is the aforementioned asodium sulfonate ofdi-sec-butyl naphthalene. Also operable are the B-sodium sulfonate ofdisec-butyl naphthalene, the a-sodium sulfonate or" di-isopropylnaphthalene, the ,B-sodium sulfonate of di-isopropyl naphthalene, theu-sodium sulfonate of diamyl naphthalene, the aor 6- sodium sulfonate oftriamyl naphthalene, the B-sodium sulfonate of diamyl naphthalene, the(X.- or fi-sodium sulfonate of tributyl naphthalene, the lx-sodiumsulfonate of dibenzyl naphthalene, the fl-sodium sulfonate of dibenzylnaphthalene, and 2,6-di-tert-butyl-4-phenyl phenol sulfonate. Theoperable range of leveling agents for the purpose of this invention is(based on yarn weight) from 0.25% to 2%, and 0.75% is the preferredconcentration.

The operable range of antioxidants for the purpose of this invention is0.25% to 2% (preferably 1%) based on yarn weight. The preferredantioxidant is 2,6-di-tert-butyl- 4 phenyl phenol.

2-(2'-hydroxy-5-methyl phenyl)benzotriazole is the preferred ultravioletlight absorber for the process of this invention, and it has anabsorption maxima on nylon of 350-360 m Other ultraviolet lightabsorbers which are also operable with nylon in the dye bath, are thosethat are also photostable, also have a useful absorption maxima onnylon, and are members of the classes comprisinghydroxyphenylbenzotriazoles, hydroxybenzophenones, and aromaticsubstituted acrylonitriles. Examples of such other operable lightabsorbers are 2,4-dihydroxybenzophenone and the ethyl ester of2-cyano-3,3-diphenyl acrylic acid. Ultraviolet light absorbers for thisinvention are operable in the range of 0.25 to 1.5% (preferably 0.5 to0.75%) based on the yarn Weight.

The operable acid dyes for this invention include C.I. Acid Yellow 29[01. 18900], C.I. Acid Brown 10, Cl. Acid Red 57, Cl. Acid Blue 23 [CI61125], C.I. Acid Blue 40, Cl. Acid Blue 41 [01. 62130], 0.1. Acid Blue58, Cl. Acid Yellow 17 [C.I. 18965], and C.I. Acid Red 37 [C.I. 17045].The concentration of dyes is not critical, but a practical operatingrange is about 0.05 to 3.00%, based on yarn weight. It has been foundthat acid dyes with molecular weights more than about 850 do notdisperse to a satisfactory degree of uniformity.

The polyamides comprehended by this invention are synthetic, linearpolyamides characterized by recurring amide linkages as an integral partof the polymer chain. These polyamides are produced by condensation ofmonoamino, monocarboxylic acids or their amide-forming derivatives, orof diamine and dicarboxylic acids or their amide-forming derivatives.Examples of the first group are polycaprolactam andpolyaminoundecanoamide. Examples of the second grou arepoly(hexamethylene adiparnide), poly(hexamethylene sebacamide),poly(m-xylylene adipamide), poly(p-xylylene sebacamide),poly(2-methylhexamethylene adipamide), and the polyamide frombis(p-aminocyclohexyl)methane and sebacic acid. Copolyamides within oramong these groups may also be employed. With these polyamides, theremay be melt-blended 2% or more by weight of a polyethylene oxide. Thepolyethylene oxide ether glycols having a molecular Weight of at least1000 are particularly suitable. Alternatively the polyethylene oxide mayhave, as end caps, either one or two radicals of oxyhydrocarbon such asmethoxy, ethoxy, phenoxy, dodecyl phenoxy, nonyl phenoxy, and the like.The capped polyethylene oxides, especially when capped by aromaticradicals, should have a molecular weight of 600 or more. The molecularweight and concentration requirements are imposed by the necessity thatenough of the oxide be added to provide a two-phase conductive system,i.e., to render the fiber antistatic. PEO compounds which have endsreactive with the polyamide are excluded since they do not form such atwo-phase system. These polyamides, with or without polyethylene oxide,may also contain conventional polyamide additives such as delusterants,pigments, plasticizers, adjuvants to increase dye ability, etc. Typicaladditives are disclosed in US. Patent Nos. 2,205,722, 2,510,777,2,887,462, and 2,345,533.

This application is a continuation-in-part of application Ser. No,315,362, filed Oct. 10, 1963.

It is apparent that many variations and modifications of the disclosedprocess may be accomplished without departing from the spirit of thepresent invention which is accordingly intended to be limited only bythe scope of the appended claims.

What is claimed is:

1. A process including the steps of dyeing, rinsing and drying nylonyarns, said dyeing step comprising heating said yarn in a bathcontaining (1) sulfonated, water-soluble, acid dyes with molecularweight less than 850; (2) 0.25 to 2.00% by Weight, based on yarn Weight,of a phenolic compound of the formula wherein R and R are alkyl groupsof sufficient bulkiness to sterically hinder the phenol group; (3) 0.25to 2.00% by weight, based on yarn weight, of a member of the class ofleveling agents consisting of 2,6-di-tert-butyl-4-phenyl phenolsulfonate and a naphthalene compound of the formula wherein R is amonovalent substituent radical selected from the group consisting ofpropyl, isopropyl, normal butyl, secondary butyl, tertiary butyl, normalamyl, sec ondary amyl, tertiary amyl, and aralkyl, m is 1-3 and R" is amonovalent radical selected from the group consisting of NH,+ and alkalimetal cations, each of the sub- 9 stituent radicals -R and SO R" beingattached at one of positions 1-8; and (4) 0.25 to 1.50% by weight, basedon yarn weight, of a photostable, ultraviolet light absorber, saidabsorber being a member of one of the classes consisting ofhydroxyphenylbenzotriazoles, hydroxybenzophenones, and aromaticsubstituted acrylonitriles.

2. The process of claim 1 wherein the phenolic compound is added as anemulsion.

3. The process of claim 1 Where the nylon yarn is a PEO-modified nylonyarn.

4. The process of claim 1 wherein the phenolic compound is2,6-di-tert-butyl-4-phenyl phenol.

5. The process of claim 4 wherein the 2,6-di-tert-butyl- 4-phenyl phenolis added as an emulsion.

6. A process including the steps of dyeing, rinsing and drying nylonyarns, said dyeing step comprising heating said yarn in a bathcontaining (1) sulfonated, water-soluble, acid dyes with molecularweight less than 850; (2) 0.25 to 2.00% by Weight, based on yarn Weight,of an emulsion of a phenolic compound of the formula wherein R is amonovalent substituent radical selected from the group consisting ofpropyl, isopropyl (normal butyl, secondary butyl, tertiary butyl, normalamyl, secondary amyl, tertiary amyl), and aralkyl, m is l-3 and R" is amonovalent radical selected from the group consisting of NH4+ and alkalimetal cations, each of the sub- It) stituent radicals R' and -SO R"being attached at one of positions 1-8.

7. The process of claim 6 wherein said phenolic compound is2,6-di-tertbutyl-4-phenyl phenol.

8. A process including the steps of dyeing, rinsing and drying nylonyarns, said dyeing step comprising heating said yarn in a bathcontaining (1) sulfonated, water-sold ble, acid dyes with molecularweight less than 850; (2) 0.25 to 2.00% by weight, based on yarn weight,of an emulsion of 2,6-di-tert-butyl-4-phenyl phenol; (3) 0.25 to 2.00%by weight, based on yarn weight, of the a-sodium sulfonate ofdi-sec-butyl naphthalene; and (4) 0.25 to 1.50% by Weight, based on yarnweight, of 2-(2-hydroxy- 5 -methyl phenyl)benzotriazole.

9. The process of claim 8 wherein the nylon yarn is a PEO-modified nylonyarn.

10. A process including the steps of dyeing, rinsing and drying nylonyarns, said dyeing step comprising heating said yarn in a bathcontaining (1) sulfonated, water-soluble, acid dyes with molecularweight less than 850; (2) 0.25 to 2.00% by weight, based on yarn Weight,of an emulsion of 2,6-di-tert-butyl-4-pl1enyl phenol; (3) 0.25 to 2.00%by Weight, based on yarn Weight, of the a-sodium sulfonate ofdi-sec-butyl naphthalene.

11. The process of claim 10 wherein the nylon yarn is a PEO-modifiednylon yarn.

References Cited UNITED STATES PATENTS Oct. 15, 1961.

D. Schmidlin, The Preparation and Dyeing of Synthetic Fibres, pp.152-159, 163 and 227-232, pub. Apr. 1, 1963 by Chapman and Hall, Ltd.,London England.

Strobel, American Dyestuif Reporter, pp. 583-588, Aug. 7, 1961.

DONALD LEVY, Primary Examiner.

